Electric switch



July 28, 1925. 1,547,884

J. F. LINDBERG ELECTRIC SWITCH Filed Aug. 30, 1922 PMs- .1, 2a, 1925.

UNITED STATE s PA lENT "o -"rice.

1 JOHN 1'. mm, nil-01S, 881G150! -'1O W01, DIE an) arm- ING comm, OICHICAGO, ILLINOIS, OOB PORATIOHOI 1151-18018.

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To allwhomitmay comma" Be it known that I, Joma' F. Immune, citizen ofthe United States, resi at Chlca in the county of Cook and tate ofIlhnois, have invented a certain new and useful Im rovement in ElectricSwitches, of which t e following is a full,-clear, and exactdescription.-

My invention relates to circuit systems and is of particular servicewhen included in a telephone receiving station, though the invention isnot to be thus limited, the present inventionbeing an improvement u nthe construction shown in my 00-. g application Serial No. 569,347 filedJune 19, 1922.

The switch of my 1 prior application included two, engaging complementalcontacts and a telephone receiver or other translate ing device havingtwo terminals engageable with the aforesaid contacts, one of thesecontacts being operable by the terminal engaging it to separate thiscontact from the contact complemental thereto. In order that a number oftele hone receivers'might be included in a wirelim receivin stationthere were provided as many suc switches as there were telephonesthrough which the telephone receiving circuit was to be closed. Thecontacts of the switches were series I in the receiving circuit andserved to establish the circuit whether one or any number of telephoneswere plugged in. It was possible, with the prior switch, to open thetelephone receiving circuit in the process of ooping in a telephonereceiver, it being the object of my present invention to avoid thispossibility.

In carrying out my present invention each switch has two sets ofengaging comple-' mental contacts, one contact of each setbeing'operable by the terminal of the telephone or other translatingdevice engaginge it to separate this contact from its conip ment. Themovable contact of each set is in circuit making and breaking relationwith the movable contact of the other set, to which end the complementof each movable contact is in permanent electrical connection with theother movable contact, being preferably formed ofthe same piece of metaltherewith.

I will explain my invention more fully by reference to the accompanyingdrawing in which Fig. 1 is a plan view of a casing and concise,

switching mechanism therein contained with aportion of the casing brokenaway, the

mechanism illustrated being constructed in accordance with the preferredembodiment of the invention; Fig. 2 is a sectional view on line 2-2 ofFig. 1; Fig. 3 is a sectional view on line 3-3 of Fig. 1, on a largerscale; Fig. 4 is a perspective viewshowin a part of the series ofswitches that are i lustrated in Fig. 2; and Fig. 5' is a diagrammaticview showing a telephone receiving circuit having switching mechanism ofmy invention and showing the manner in which twotelephones may be loopedinto circuit.

Like parts are indicated by similar characters of reference throughoutthe difl'erent figures.

The telephone receiving circuit, such as the-complete circuit of a radiooutfit, has its sides land 2 respectively terminating in terminals 3 and4. U-shaped spring members 5, 6, 7 and 8 are interposed between thesetwo terminals. The sides or arms 9, 1'0, 11, 12, 13, 14, and 16constitute movable or operable switch contacts. The terminals 3 and 4have extensions 17 and 18 which are similar in construction to the sidesof the U-shaped spring members and also constitute operable, or movablecontacts. These contacts respectively have as their complementalcontacts the bars 19, 20, 21, 22, 23, 24, 25, 26, 27 and 28. Thecomplemental contacts 17 and '27 constitute one set and the complementalcontacts 9 and 19 constitute another set, both of these sets.comprising'one switch. The movable contact -17 of the set 17, 27, is incircuit making and breaking relation with the movable 1 contact 9 of theother set, the contacts 9 and 27 being preferably stamped out of thesame piece of sheet metal. Similarly, the movable contact 9 of the set9, 17 is 1n circuit making and breaking relation with the movablecontact 17 of the first set, the contacts 19 and 17 being stamped out ofanother piece of sheet metal. I

The movable contacts 10 and 11 and their stationa complements 20 and 21form another swltch similar to the switch composed of the contacts 9 and17 and their stationary 0 The terminal 3 and the contacts 17 and 19 mabe formed out of one piece of metal where ythe contacts 17 and 19 are inpermanent electrical connection. The same 1s also true of the terminal 4and the contacts 18 and 26. The adjacent movable contacts 9 and 10 areelectrically connected constitutingiaas stated, sides of U-shaped springmem ers, the same being true of the movable contacts 11, 12; 13, 14; and15, 16. The stationary contacts 21' and 27 are formed in the same pieceof metal with the movable contacts 9 and 10 so as to be electricallyconnected therewith. So also are the stationary contacts and 23 formedin the same piece of metal with the contacts 11 and 12, stationarycontacts 22 and 25 with the movable contacts 13 and 14, and thestationary contacts 24 and 28 with the movable contacts 15 and 16, forthe same urpose.

I have illustrated two head telep ones 29 and 30 respectively havingterminal tags or small plugs 31, 32 and 33, 34.

When the telephones are out of circuit the various switches, being inseries, co-operate to maintain the circuit closed. When one telephone,or any number of telephones, are included in circuit they perform thecircuit maintaining function that was effected by the movable contactsthat are shifted by the terminals of the telephones. Any one movablecontact may be shifted by a telephone plug without breakin the circuiteven though the complement 0 such plug is" not in circuit. This is dueto the fact that the movable contactof each of the two sets of contactsthat comprise a switch is in circuit making and breaking relation withthe movable contact of the other set of such switch by placing thecomplement of each such movable contact in permanent electricalconnection with the other movable contact,

contact 9 because the complement 27 of the contact 17 is formed in t esame piece of metal with the contact 9 and the contact 9 is in circuitmaking, and breaking relation with the contact 17 ecause the complement19 of the contact 9 is formed in the same .piece of metal with thecontact 17.

While I have herein shown and particularly described the preferredembodiment of my invention I do not wish to be limited to the precisedetails of construction shown as changes may readily be made withoutdeparting from the spirit of my invention, but having thus described myinvention I claim as new and desire to secure by Letters Patent thefollowing:-

1. A circuit closing switch including two sets of engaging contacts eachset including an operable contact and a contact complemental thereto,the complement of the operable contact of each set being electricallyconnected with the operable contact of the 7 other set, each operablecontact and the complement to the other! operable contact being formedand relatively positioned to receive a connecting plug therebetween foroperating the operable contact.

2. A plurality of switches connected in series, each switch includingtwo sets of engaging contactseach set including an operable contact anda contact complemental thereto, the complement of the operable contactof each set of contacts of each switch being electrically connected withthe operable contact of the other set of such switch, each operablecontact and the complement to the other operable contact being formedand relatively positioned to receive a connecting plug therebetween foroperating the operable contact.

In witness whereof, I hereunto subscribe JOHN F. LINDBERG.

-my name this 6th day of July A. D., 1922.

as described. Thus the contact 17 is in circuit making andbreaking-relation with the

